The journal of pain : official journal of the American Pain Society
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Policies that address opioid dose limits may help to decrease high-risk opioid prescribing. We evaluated 3 sequential and progressive decreases in high-dose (HD) opioid limits implemented by Massachusetts Medicaid over 15 years. The study population included members ages 18 to 64 years with ≥1 claim for a schedule II opioid between January 2002 and March 2017. ⋯ The natural log of the AD_MED decreased among members after implementation of 3 sequential and progressive HD prior authorization limits, as did the percentage of members exceeding each of the HD limits. PERSPECTIVE: This study demonstrates the longitudinal impact of a prior authorization policy-based HD limit in a Medicaid population. This study contributes to options for policymakers and other Medicaid programs as a potential strategy to assist in addressing the opioid epidemic.
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Spatial integration of parts of the body is impaired in patients with complex regional pain syndrome (CRPS). Because the training of mental rotation (MR) has been shown to be among the effective therapy strategies for CRPS, impairment of MR is also important for the pathophysiological understanding of CRPS. The aim of this study was to evaluate whether differences in the neural representation of MR occur between patients with CRPS and healthy controls (HC). ⋯ Regression analysis for the CRPS group emphasized the importance of putamen and nucleus accumbens activation for MR performance. This study highlights the reduced access of patients with CRPS for mental resources modulating arousal, emotional response, and subcortical sensorimotor integration. PERSPECTIVE: This study localized the underlying neural responses for impaired mental rotation in patients with complex regional pain syndrome as a decrease in basal ganglia (putamen) and nucleus accumbens activation.
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The present study investigated the role of the amygdala N-methyl-d-aspartate (NMDA) receptors/nitric oxide synthase pathway in morphine-induced anti-allodynia. Concurrently with the bilateral cannulation of the central amygdala, chronic constriction of the sciatic nerve was performed on male Wistar rats. Morphine (3-5 mg/kg) was administered intraperitoneally to induce anti-allodynia. ⋯ PERSPECTIVE: Neuropathic pain is difficult to treat and the exact mechanisms remain unknown. This article suggests the importance of the amygdala glutamatergic and nitric oxide systems in morphine-induced anti-allodynia. These findings might be used in clinical studies to reach a better understanding of neuropathic pain mechanisms and treatment.